Refer to the exhibit. An administrator configures a router to stop using a particular default route if the DNS server 8.8.8.8 is not reachable through that route.
However, this configuration did not work as desired and the default route still works even if the DNS server 8.8.8.8 is unreachable. Which two configuration changes resolve the issue? (Choose two.)
To resolve the issue, using a separate IP SLA probe and track object for every static route ensures each route is monitored independently. This addresses the need for different monitoring instances per route. Additionally, associating every IP SLA probe with the proper WAN address of the router ensures the probes are checking connectivity through the correct interfaces, preventing false positives from other routes remaining active. This configuration accurately targets the correct paths and ensures proper failover mechanisms.
Correct: B - Both static routes must have a separate Track object and IP SLA probe. C - Each SLA probe must originate from a different ISP, therefore a different IP address. Wrong: A - Only a separate Track object won't help with anything, we need also a separate IP SLA probe. D - This is redundant, the router knows which interface to use for both next hops (based on ARP and MAC address table). E - This is just messy and not needed, we just need to set a different source for each probe (answer C).
I would vote for B and C. Setting the static route to 8.8.8.8 for both ISP doesn't make sense. It would make sense if it is only one static route for that.
Im going for B and C, because the alternative E it's isn't needed, with the default route u already have communication with google DNS, so you only need to separate the tracks between static routes and WAN's
D & E are correct
https://community.cisco.com/t5/routing/ip-sla-tracking-a-far-ip/td-p/1971337
im going with B & C
It is not clearly described what they want to configure with "E". It could be a valid option with the correct configuration. Based on this: https://community.cisco.com/t5/routing/ip-sla-tracking-a-far-ip/td-p/1971337 The first two static routes are there to make sure that the tested IP address inside the ISP1 is truly reached only via link to ISP1, and if that link is down, then the pings are going to be thrown away (this is to prevent pinging 8.8.8.8 via ISP2 thanks to the default route). ip route 8.8.8.8 255.255.255.255 Ethernet0/0 10.0.0.1 ip route 8.8.8.8 255.255.255.255 Null0 2 ip sla 1 icmp-echo 8.8.8.8 source-interface Ethernet0/0 threshold 800 timeout 1000 frequency 30 ip sla schedule 1 start-time now life forever track 1 rtr 1 reachability ip route 0.0.0.0 0.0.0.0 10.0.0.1 track 1 ip route 0.0.0.0 0.0.0.0 20.0.0.1 2
This way, a static route to 8.8.8.8/32 should be set only via primary ISP. Not for both ISPs. This makes "E" incorrect.
Question: "icmp-echo 8.8.8.8 source-interface Ethernet0/0" Would the device in this case only use the source IP of the interface or only allow packets going outbound (so if a route lacks, the packets will not even be send outbound). Anyway, in my opinion there is a difference between a route, a source interface and the actual route used for the test icmp packet. Anyway, i guess i need to lab this one to really understand how the source-interface part behaves.